Final answer:
Feedback inhibition or autoregulation is the process by which an amino acid regulates the synthesis of components used to produce its biosynthesis pathway, often by affecting gene expression through interactions with transcription factors or enzymes.
Step-by-step explanation:
The term for an amino acid regulating the expression of components used to synthesize it is known as feedback inhibition or autoregulation. This process occurs when the end product of a pathway inhibits an enzyme involved in its own synthesis pathway, thereby controlling the production of itself through gene expression.
In the context of protein synthesis, transcription factors play a critical role in regulating gene expression. These factors can either enhance or suppress the transcription of genes. When an amino acid exerts control over its own synthesis, it may influence the transcription factors that regulate the operons involved in its biosynthetic pathway. For example, the amino acid tryptophan can bind to the repressor protein of the trp operon in bacteria, which in turn binds to the operator, blocking the transcription of genes required for its own synthesis.
Another mechanism involves transfer RNA (tRNA) and aminoacyl tRNA synthetases, which add the correct amino acid to the tRNA, a process crucial for translation. Gene expression can be regulated at other stages as well, including during mRNA translation and protein processing.